Type ))))
Animate, Scale ->250%
More options-> Grouping Alignment->y-Axis to sit in the middle
Advanced-> Shape->Ramp up
To simulate the pulse effect select a new opacity animator->Opacity 0%
Open the Range selector and set the start to 0% and make a keyframe, move to 1 sec -> 100%
For the backwards select the animator and Add:->Selector->Range
Start:100%, End: 0%, Offset:-100%
Go back some frames and set a KF for the offset
Go to 2sec an set a KF to 0%